/// <summary>
/// Computes the isotope distribution of the tracer
/// </summary>
private void ComputeMasses()
{
var res = Workspace.GetAminoAcidFormulas();
if (!AminoAcidSymbol.HasValue)
{
// If the tracer is a single element, then its mass is just the normal mass
// of the element plus the mass shift.
TraceeMasses = res.GetMassDistribution(Molecule.Parse(TraceeSymbol), 0);
double tracerMass = TraceeMasses.MostAbundanceMass + DeltaMass;
TracerMasses = MassDistribution.NewInstance(new Dictionary <double, double> {
{ tracerMass, 1.0 }
}, 0, 0);
return;
}
// If the tracer is an amino acid, get the masses of the amino acid, and
// add in atoms with the correct mass shift.
var heavyMasses = new Dictionary <double, double>();
heavyMasses.Add(0, 1 - AtomPercentEnrichment / 100);
heavyMasses.Add(DeltaMass / AtomCount, AtomPercentEnrichment / 100);
const string tempName = "Temp";
var isotopeAbundances = res.IsotopeAbundances.SetAbundances(
tempName, MassDistribution.NewInstance(heavyMasses, 0, 0));
res = res.SetIsotopeAbundances(isotopeAbundances);
var formula = Molecule.Parse(res.Formulas[AminoAcidSymbol.Value]);
var tracerFormula = Molecule.Parse(formula + tempName + AtomCount);
TraceeMasses = res.GetMassDistribution(formula, 0);
TracerMasses = res.GetMassDistribution(tracerFormula, 0);
}
/// <summary>
/// Synchronizes a single <see cref="MassDistribution"/> object with corresponding
/// masses from a <see cref="BioMassCalc"/>.
/// </summary>
private static MassDistribution SynchDist(MassDistribution massDist,
double monoMassCalc, double secondMassCalc, double thirdMassCalc)
{
var massDistOrdered = massDist.MassesSortedByAbundance();
if (EqualDistMasses(massDistOrdered, monoMassCalc, secondMassCalc, thirdMassCalc))
{
return(massDist);
}
var dictFixDist = new Dictionary <double, double>(massDist);
ReplaceMass(dictFixDist, massDistOrdered, 0, monoMassCalc);
ReplaceMass(dictFixDist, massDistOrdered, 1, secondMassCalc);
ReplaceMass(dictFixDist, massDistOrdered, 2, thirdMassCalc);
return(MassDistribution.NewInstance(dictFixDist, 0, 0));
}
public IsotopeDistInfo(MassDistribution massDistribution,
TypedMass monoisotopicMass,
Adduct adduct,
Func <double, double> calcFilterWindow,
double massResolution,
double minimumAbundance)
{
_monoisotopicMass = monoisotopicMass;
_adduct = adduct.Unlabeled; // Don't reapply explicit isotope labels
// Get peak center of mass values for the given resolution
var q1FilterValues = MassDistribution.NewInstance(massDistribution, massResolution, 0).Keys.ToList();
// Find the monoisotopic m/z and make sure it is exactly the expected number
double monoMz = _adduct.MzFromNeutralMass(_monoisotopicMass);
double monoMzDist = monoMz;
int monoMassIndex = 0;
for (int i = 0; i < q1FilterValues.Count; i++)
{
double peakCenterMz = q1FilterValues[i];
double filterWindow = calcFilterWindow(peakCenterMz);
double startMz = peakCenterMz - filterWindow / 2;
double endMz = startMz + filterWindow;
if (startMz < monoMz && monoMz < endMz)
{
monoMzDist = q1FilterValues[i];
q1FilterValues[i] = monoMz;
monoMassIndex = i;
break;
}
}
// Insert a M-1 peak, even if it is not expected in the isotope mass distribution
if (monoMassIndex == 0 && q1FilterValues.Count > 1)
{
// Use the delta from the original distribution monoMz to the next peak
q1FilterValues.Insert(0, monoMz + monoMzDist - q1FilterValues[1]);
monoMassIndex++;
}
if (!q1FilterValues.Any())
{
// This should never happen, but just in case it does happen, we safely exit the constructor
ExpectedPeaks = ImmutableList.Singleton(new MzRankProportion(monoMz, 0, 1.0f));
MonoMassIndex = BaseMassIndex = 0;
return;
}
var signedQ1FilterValues = q1FilterValues.Select(q => new SignedMz(q, adduct.AdductCharge < 0)).ToList();
// Use the filtering algorithm that will be used on real data to determine the
// expected proportions of the mass distribution that will end up filtered into
// peaks
// CONSIDER: Mass accuracy information is not calculated here
var key = new PrecursorTextId(signedQ1FilterValues[monoMassIndex], null, null, ChromExtractor.summed);
var filter = new SpectrumFilterPair(key, PeptideDocNode.UNKNOWN_COLOR, 0, null, null, false, false);
filter.AddQ1FilterValues(signedQ1FilterValues, calcFilterWindow);
var expectedSpectrum = filter.FilterQ1SpectrumList(new[] { new MsDataSpectrum
{
Mzs = massDistribution.Keys.ToArray(), Intensities = massDistribution.Values.ToArray(), NegativeCharge = (adduct.AdductCharge < 0)
} });
int startIndex = expectedSpectrum.Intensities.IndexOf(inten => inten >= minimumAbundance);
if (startIndex == -1)
{
// This can happen if the amino acid modifications are messed up,
// and the peptide mass is negative or something.
ExpectedPeaks = ImmutableList.Singleton(new MzRankProportion(monoMz, 0, 1.0f));
MonoMassIndex = BaseMassIndex = 0;
return;
}
// Always include the M-1 peak, even if it is expected to have zero intensity
if (startIndex > monoMassIndex - 1)
{
startIndex = monoMassIndex - 1;
}
if (startIndex < 0)
{
startIndex = 0;
}
int endIndex = expectedSpectrum.Intensities.LastIndexOf(inten => inten >= minimumAbundance) + 1;
int countPeaks = endIndex - startIndex;
var listProportionIndices = new List <KeyValuePair <float, int> >(countPeaks);
for (int i = 0; i < countPeaks; i++)
{
listProportionIndices.Add(new KeyValuePair <float, int>(
expectedSpectrum.Intensities[i + startIndex], i));
}
// Sort proportions descending.
listProportionIndices.Sort((p1, p2) => Comparer.Default.Compare(p2.Key, p1.Key));
// Set proportions and ranks back in the original locations
var expectedProportionRanks = new KeyValuePair <float, int> [countPeaks];
for (int i = 0; i < countPeaks; i++)
{
expectedProportionRanks[listProportionIndices[i].Value] =
new KeyValuePair <float, int>(listProportionIndices[i].Key, i + 1);
}
MonoMassIndex = monoMassIndex - startIndex;
// Find the base peak and fill in the masses and proportions
var expectedPeaks = new List <MzRankProportion>();
for (int i = 0; i < countPeaks; i++)
{
float expectedProportion = expectedProportionRanks[i].Key;
int rank = expectedProportionRanks[i].Value;
expectedPeaks.Add(new MzRankProportion(q1FilterValues[i + startIndex], rank, expectedProportion));
if (expectedProportion > expectedProportionRanks[BaseMassIndex].Key)
{
BaseMassIndex = i;
}
}
ExpectedPeaks = expectedPeaks;
}
public IsotopeDistInfo(MassDistribution massDistribution,
double monoisotopicMass,
bool isMassH, // Is monoisotopicMass M+H, or just M as in small molecule use?
int charge,
Func <double, double> calcFilterWindow,
double massResolution,
double minimumAbundance)
{
_monoisotopicMass = monoisotopicMass;
_charge = charge;
_isMassH = isMassH;
// Get peak center of mass values for the given resolution
var q1FilterValues = MassDistribution.NewInstance(massDistribution, massResolution, 0).Keys.ToList();
// Find the monoisotopic m/z and make sure it is exactly the expected number
double monoMz = isMassH ? SequenceMassCalc.GetMZ(_monoisotopicMass, _charge) : BioMassCalc.CalculateIonMz(_monoisotopicMass, _charge);
double monoMzDist = monoMz;
int monoMassIndex = 0;
for (int i = 0; i < q1FilterValues.Count; i++)
{
double peakCenterMz = q1FilterValues[i];
double filterWindow = calcFilterWindow(peakCenterMz);
double startMz = peakCenterMz - filterWindow / 2;
double endMz = startMz + filterWindow;
if (startMz < monoMz && monoMz < endMz)
{
monoMzDist = q1FilterValues[i];
q1FilterValues[i] = monoMz;
monoMassIndex = i;
break;
}
}
// Insert a M-1 peak, even if it is not expected in the isotope mass distribution
if (monoMassIndex == 0 && q1FilterValues.Count > 1)
{
// Use the delta from the original distribution monoMz to the next peak
q1FilterValues.Insert(0, monoMz + monoMzDist - q1FilterValues[1]);
monoMassIndex++;
}
if (!q1FilterValues.Any()) // As is small molecule docs with mz values only, no formulas
{
return;
}
// Use the filtering algorithm that will be used on real data to determine the
// expected proportions of the mass distribution that will end up filtered into
// peaks
// CONSIDER: Mass accuracy information is not calculated here
var key = new PrecursorTextId(q1FilterValues[monoMassIndex], null, ChromExtractor.summed);
var filter = new SpectrumFilterPair(key, PeptideDocNode.UNKNOWN_COLOR, 0, null, null, null, null, 0, false, false);
filter.AddQ1FilterValues(q1FilterValues, calcFilterWindow);
var expectedSpectrum = filter.FilterQ1SpectrumList(new[] { new MsDataSpectrum
{
Mzs = massDistribution.Keys.ToArray(), Intensities = massDistribution.Values.ToArray()
} });
int startIndex = expectedSpectrum.Intensities.IndexOf(inten => inten >= minimumAbundance);
if (startIndex == -1)
{
throw new InvalidOperationException(
string.Format(Resources.IsotopeDistInfo_IsotopeDistInfo_Minimum_abundance__0__too_high,
minimumAbundance));
}
// Always include the M-1 peak, even if it is expected to have zero intensity
if (startIndex > monoMassIndex - 1)
{
startIndex = monoMassIndex - 1;
}
if (startIndex < 0)
{
startIndex = 0;
}
int endIndex = expectedSpectrum.Intensities.LastIndexOf(inten => inten >= minimumAbundance) + 1;
int countPeaks = endIndex - startIndex;
var listProportionIndices = new List <KeyValuePair <float, int> >(countPeaks);
for (int i = 0; i < countPeaks; i++)
{
listProportionIndices.Add(new KeyValuePair <float, int>(
expectedSpectrum.Intensities[i + startIndex], i));
}
// Sort proportions descending.
listProportionIndices.Sort((p1, p2) => Comparer.Default.Compare(p2.Key, p1.Key));
// Set proportions and ranks back in the original locations
var expectedProportionRanks = new KeyValuePair <float, int> [countPeaks];
for (int i = 0; i < countPeaks; i++)
{
expectedProportionRanks[listProportionIndices[i].Value] =
new KeyValuePair <float, int>(listProportionIndices[i].Key, i + 1);
}
// TODO: Can this be discarded?
// MassDistribution = massDistribution;
MonoMassIndex = monoMassIndex - startIndex;
// Find the base peak and fill in the masses and proportions
var expectedPeaks = new List <MzRankProportion>();
for (int i = 0; i < countPeaks; i++)
{
float expectedProportion = expectedProportionRanks[i].Key;
int rank = expectedProportionRanks[i].Value;
expectedPeaks.Add(new MzRankProportion(q1FilterValues[i + startIndex], rank, expectedProportion));
if (expectedProportion > expectedProportionRanks[BaseMassIndex].Key)
{
BaseMassIndex = i;
}
}
ExpectedPeaks = expectedPeaks;
}
